Personally, I think the time passage is perfect. It can feel a little dragged out early on when your stamina is lower and you can't do as much in the day, and can feel a little too fast when you've got the outfit and more stamina, but I like that you have to approach each day with at least some semblance of a plan and prioritization.
Definitely keep stamina. I agree that there need to be more stamina replenishing items, or at least, for now, that those already in the game should be adjusted. More complex food, for example, should replenish more stamina. So the cookable stew and salty catfish should both have higher stamina regen, as should the granny's pumpkin pie, since you have to buy the ingredients (peppers and salt) or the pie outright. Apples would be a great early-game stamina replenishing item if it wasn't so hard to get even one or two of them down. Perhaps having 1-2 apples fall off each tree each day that you can pick up for no stamina cost, but you can still try kicking the trees to get more if you wanted.
Personally, I've found that I spend a good portion of time in between abandoned mine runs farming llamas, sea urchins, and snails for their meat and making grilled meat from them so I can have stamina replenishing items when I go spelunking. It takes a few days to build up a good collection of them, but I usually can go digging for about 12-14 ingame hours with a stack of 8-10 grilled meat and a few apples that I've gathered while making resource node rounds. As for waiting for the furnaces... I just always keep them running, even when I don't have a need. Right now I've got three of them going, and I ALWAYS keep copper burning in at least one of those. The second is usually running bronze bars or stone bricks, and the third is sometimes empty so I can toss in smaller batches of things as needed, such as for glass or extra copper. Personally, I LOVE that it takes time for each to process - it feels less like a boring instant-gratification mobile game that way, and kind of forces you to go out and do other things in the meantime.